P - R
PAN-ALIC
Lake-ice cover has been shown to be a robust indicator of climate variability and change. Recent studies have demonstrated that break-up dates, in particular, have been occurring earlier in many parts of the Northern Hemisphere over the last 50 years in response to warmer climatic conditions in the winter and spring seasons. Break-up dates, and to a lesser extent freeze-up dates, have been shown to be strongly related to the variability and trends in the 0oC isotherm dates as well as large-scale atmospheric and oceanic circulation patterns (teleconnections), particularly in western North America. The impacts of recently documented trends in air temperature and winter precipitation over the last five decades and those projected by global climate models could be significant on the timing and duration of ice cover (and on ice thickness) on Arctic lakes. This could, in turn, have an important feedback effect on energy, water, and biogeochemical cycling in various regions of the Arctic. How ice phenology (i.e. freeze-up/break-up dates, ice cover duration) and ice thickness have changed over the last five decades, and what will likely be the impacts of projected 21st century climate warming on ice cover for lakes of various depths in different regions of the pan-Artic domain are questions that must be examined in order to gain a deeper understanding of climate-lake interactions in the Arctic. The proposed research project will seek to answer these pressing questions. The overall goal will be to provide a pan-Arctic view of the temporal and spatial variability and trends in lake ice cover in relation to teleconnection patterns during the second half of the 20th century, and plausible scenarios of the response of lake ice cover to projected future climate. The analyses from this research will provide a better understanding of the impacts of the large-scale atmospheric and oceanic oscillations on past lake-ice conditions. This, along with modelled projections of future climate, will offer insight into future regional changes to lake-ice characteristics and resultant hydrologic and ecologic impacts over various regions of the Arctic. The goal of the proposed project reflects very well the goals and objectives of the US-lead initiative Study on Environmental Arctic Change (SEARCH) in detecting and elucidating the recent changes in the Arctic and their impacts on human lives and activities. It is also directly related to the overarching goal of the pan-Arctic Community-wide Hydrological Analysis and Monitoring Program (Arctic-CHAMP) which seeks to better understand and predict the arctic hydrologic cycle. More specifically, the proposed research will provide observations and modeling results which will help fill current gaps in understanding the pan-Arctic hydrological cycle. This project is of direct relevance to three of the five main scientific themes of IPY: 1) to determine the present environmental status of polar regions by quantifying their spatial and temporal variability; 2) to quantify, and understand, past and present environmental and human change in polar regions in order to improve predictions; and 3) to advance our understanding of polar – global teleconnections on all scales, and of the processes controlling these interactions. Results of this project will contribute valuable information to other IPY projects, most notably “The State and Fate of the Cryosphere”, as well as international climate change programs (e.g. Climate and Cryosphere (CliC), Global Climate Observing System (GCOS), Integrated Global Observing System (IGOS) – Cryosphere) and assessments such as the International Panel on Climate Change (IPCC). Ultimately, this project will not only deliver a pan-Arctic view of the response of lake ice to past and future climate conditions, but will also highlight the impacts of ice cover changes on regional climate, hydrology, lake ecology, and Arctic communities. Summary provided by http://classic.ipy.org/development/eoi/proposal-details.php?id=423